GemRB-git with Clang 3.1

[Traveler]

Do you care if GemRB compiles with clang or is it non-issue? I needed to delete '-g' flag, as

by default unused flags stops clang.

 

http://pastebin.com/3gANtNeD

 

P.S. As a side issue, this forum's textboxes are driving me crazy, apparently middle button paste

doesn't work as it should in Opera.

[lynx]

heh, blame ffmpeg. And yes, the pasting bug is annoying, though it sometimes works.

 

clang doesn't use -g at all??

[SyntaxError]

We build the mac/ios builds with clang 3.1 and the g option doesnt cause a problem for me. (tho i suppose it may be ignored)

[Traveler]

Maybe you have -Qunused-arguments added? By default unused flags stops compiling.

[lynx]

or he disabled -Werror

[Traveler]

To clarify, -g is supported by clang, just something within GemRB made clang stop with '-g' unused warning (error in this case).

[SyntaxError]

no i have -werror on. I also get no build warnings whatsoever.

 

can you clarify what the error is? (I'm using dwarf with o0 btw)

[Traveler]

Sure,

 

[ 67%] Building CXX object gemrb/core/CMakeFiles/gemrb_core.dir/System/String.cpp.o

Linking CXX shared library libgemrb_core.so

c++: error: argument unused during compilation: '-g'

*** [gemrb/core/libgemrb_core.so] Error code 1

1 error

*** [gemrb/core/CMakeFiles/gemrb_core.dir/all] Error code 2

1 error

*** [all] Error code 2

1 error

 

$ clang -v

 

FreeBSD clang version 3.1 (branches/release_31 156863) 20120523 (basically Clang 3.1)

 

It supports -g flag per se.

[SyntaxError]

for the -g option to be used dont you also need to supply other options? ill look later to see what options im using.

[lynx]

Not for gcc, though you could specify the format you want the debug info in. Looks more like it tried to use it at link time, which makes no sense afaik.

[Traveler]

The difference could be, that gcc ignores '-g' flag during linking and clang stops if some flag is not recognized (or doubled also? I'm not sure.), and by default the same flags (-O2, -g probably) are using during compiling and linking.

[Traveler]

wtf?

 

http://llvm.org/bugs/show_bug.cgi?id=8611

[lynx]

Maybe it resurfaced or wasn't fixed for all platforms. Something to ask them about.

[Traveler]

Ok, to sum up:

 

1. Clang stops if some flag is not recognized (this is expected and wanted behaviour in Clang).

2. Lots of projects include in one way or another CFLAGS in linking. This wasn't a problem, since GCC

usually ignored not recognized flags, and still does so for '-g' stated during linking.

3. While apparently some time ago Clang developers wanted to allow benign -g during linking, FreeBSD

clang version 3.1 (which is latest) is still strict here.

 

Probably 'correct' way would be to trace where {$CFLAGS} is included in linking and stop doing it, as it

does nothing at best.

[SyntaxError]

lynx, good eye on the linking bit i completely missed that.

 

now i suddenly remember having this problem with building on mac using cmake.

IIRC I had to monkey with the cflags prior to linking to remove that stuff because cmake uses it for both compiling and linking

 

however i fixed it, it probably is a simple matter of changing if(mac) to if(clang)